Tuesday night I had the opportunity to learn more about this delicious* (OK, not literally) new product. Alison Lee presented one of her fabulous craftcast classes featuring Tim McCreight, with guest comments by Celie Fago, Barbara Becker Simon, and Jeanette Landenwitch. They shared their experiences which provided a lot of insight into using the new material.
Taking a class, (online or otherwise) is a great way to cut your learning curve. I learned some great tips. For some reason, people thought this class was going to be some kind of "infomercial." It was anything but... nobody was selling anything - just sharing their experiences with the material. And we all got the info we needed to get rolling...
|Celie Fago's carved ring|
|Barbara Simon's carved bangle|
|Celie Fago tear-away ring|
So now I'll get to carve this new stuff and I can't wait! (Hurry UPS!) It takes texture just as beautifully as other versions of PMC - and can accept Keum-boo, though it may be a little more challenging to apply than the fine silver. Celie mentioned that this ring required a little patching... still, it works well enough - and as Celie said "it sticks" which, after all, is the bottom line.
For an hour and thirty minutes we got to hear all about PRO - and ask questions too... there were a lot of questions with about 100 attendees in the class!
Just a quick synopsis:
- This stuff is STRONG! The various strength tests show it to be far superior to any previous PMC formula. You can work thinner without sacrificing strength.
- Fired in carbon - 1400ºF for 1 hour (or more, depends on several variables - see the notes). Pieces should be about 1/2" apart (10 cm) and have that much carbon on top and below. Too much carbon will inhibit sintering.
- Shrinkage is about 15-20%. A bit more than PMC 3 or PMC +
- Hattie Sanderson added that she sizes rings 3.5 sizes larger to accommodate the shrinkage.
- Can't be directly mixed with the other clays, but can be joined with the other clays and fired. Requires a shelf firing/carbon firing combo (30 mins shelf 1000ºF; 30 mins 1400ºF carbon).
- The slip is easy to make - just add water (and lavender oil too - Tim has used this on the greenware as well as the fired clay).
- As noted above, will accept Keum-boo, no prep necessary.
- Can be enameled. Using the two-stage shelf firing/carbon firing method is best (per Jeanette Landenwitch). This is not unlike the experience I found with the COPPRclay. Enamel adhered best when it was shelf fired prior to carbon firing.
- Wash tools between using for other silver clays, just as you would for base metal clays. Do not share sanding tools, as these can load up with material and contaminate your regular clay.
- The melting point is lower (typical of an alloy) so you have to be sure not to fire with original clay (requiring 1650ºF firing) or use hard solder (flows above the melting point).
And there's more... when I actually get a chance to play with it, I'll be happy to share what I learn too. Cutting edge stuff - literally, Tim showed a knife he'd made that actually held an edge - pretty cool!
* Barbara Becker Simon's description